Design for a boat deck



FIG. 1 is a top, front and right side perspective view of a boat deck showing our new design, the broken lines are for illustrative purposes only and form no part of the claimed design;

FIG. 2 is a top, rear and left side perspective view thereof, the broken lines are for illustrative purposes only;

FIG. 3 is a top plan view thereof;

The left of the boat deck is a mirror image of the right thereof. The underside of the boat deck is plain and unornamented. 

The ornamental design for a boat deck, as shown and described. 